Command using patterns that extends an extension point

Hi,
I have a pattern with an extension point and several patterns that implement this extension point.
I would like to create a wizard that allows from the first pattern to choose one of the patterns that implement the extension point.
Once the pattern is chosen, a command should be able to unfold the extension pattern.
I read in the guidance explorer the following:
"Because it is not known at design-time which pattern (from another toolkit) will plug into instances of this pattern, you cannot ‘Auto-Create’ instances of other patterns. However, you can create custom commands that "
Unfortunately the sentence is incomplete...